Scatterer Surface Design for Wave Scattering Application

In this paper, radio wave scattering is considered and an optimal scatterer surface is realized. For this purpose, an ultrawideband and high-efficiency polarization converter unit cell is proposed. Here, the proposed polarization converter unit cell and its mirror are combined to provide 180° phase difference for scattering purposes. The desired combination of unit cells which produces uniform scattering pattern and maximum wave attenuation achieved employing group search optimization (GSO) algorithm. For the problem at hand, the GSO optimization algorithm is presented in bilevel format including master and slave levels. Simulation and experimental results showed that the 10 dB bandwidth of normalized radar cross section (RCS) reduction is achieved in ultrawideband ranging from 5.5 to 20.51 GHz with a fractional bandwidth of 115%, assuring a favorable performance of the proposed method. In addition, a wide-angle bistatic RCS reduction over a wide frequency band is attained.